US6421541B1 - Adaptable bandwidth - Google Patents
Adaptable bandwidth Download PDFInfo
- Publication number
- US6421541B1 US6421541B1 US09/488,314 US48831400A US6421541B1 US 6421541 B1 US6421541 B1 US 6421541B1 US 48831400 A US48831400 A US 48831400A US 6421541 B1 US6421541 B1 US 6421541B1
- Authority
- US
- United States
- Prior art keywords
- bandwidth
- central node
- data rate
- link
- terminal
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
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Classifications
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04W—WIRELESS COMMUNICATION NETWORKS
- H04W52/00—Power management, e.g. TPC [Transmission Power Control], power saving or power classes
- H04W52/04—TPC
- H04W52/18—TPC being performed according to specific parameters
- H04W52/26—TPC being performed according to specific parameters using transmission rate or quality of service QoS [Quality of Service]
- H04W52/265—TPC being performed according to specific parameters using transmission rate or quality of service QoS [Quality of Service] taking into account the quality of service QoS
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L1/00—Arrangements for detecting or preventing errors in the information received
- H04L1/0001—Systems modifying transmission characteristics according to link quality, e.g. power backoff
- H04L1/0023—Systems modifying transmission characteristics according to link quality, e.g. power backoff characterised by the signalling
- H04L1/0025—Transmission of mode-switching indication
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04W—WIRELESS COMMUNICATION NETWORKS
- H04W52/00—Power management, e.g. TPC [Transmission Power Control], power saving or power classes
- H04W52/04—TPC
- H04W52/18—TPC being performed according to specific parameters
- H04W52/26—TPC being performed according to specific parameters using transmission rate or quality of service QoS [Quality of Service]
- H04W52/267—TPC being performed according to specific parameters using transmission rate or quality of service QoS [Quality of Service] taking into account the information rate
Definitions
- the present invention relates to a method for attenuation compensation in a communication system, and more exactly to a method to adapt the band-width as a result of signal attenuation.
- a further problem is that many satellite systems are interference limited, which implies that the entire dynamic range for weather changes and eventual changes in distance between transmitter and receiver must be compensated by a regulation of the transmitter output power. Dynamically this leads to that the transmitter working point for certain cases must be changed by more than 20 dB.
- JP 63-262924A discloses a device for satellite communication, in which a decision circuitry calculates the excess of a precipitation attenuation over the range of power control and then changes the data rate to satisfy the prescribed line quality.
- Another document, JP 41-3044317A also contemplates a way to keep the actual quality of a satellite communication line constant at all times by measuring a BER (bit error rate) of a loop-backed pilot signal and adjust transmission speed of the pilot signal to maintain a preset bit error rate independent of the channel attenuation. The result of the pilot signal measurement is then controlling the transmission power.
- BER bit error rate
- Still another document JP 21-13653A describes a method to effectively utilize frequencies in a simple constitution, and to effectively make them to function for various types of fading by providing a large capacity transmitting system and a small capacity transmitting system.
- the receiving condition is supervised by means of a receiving system, and a switching of transmitting systems between the transmitting side and receiving side takes place assisted by a switching control signal being the supervisory result.
- the small capacity transmitting system utilizes a narrowed transmission bandwidth. However the regulation takes place only in two steps and requires the equipment to be doubled.
- the present invention discloses a method in which the bandwidth is decreased instead of increasing EIRP in order maintain a same power density per Hz at the receiver in cases of poor weather conditions resulting for instance in precipitation attenuation or fading.
- This also leads to a reduced data transmission rate for the specific channel due to the poor weather conditions, but different from the state of the art, the reduced bandwidth instead allows more subscribers to be connected.
- the dynamics of the transmitter output power regulation will only need to cover the steps of bandwidth regulation. If the bandwidth is reduced, for instance, by dividing by a factor two it will be enough with an order of 3 dB dynamics or ⁇ 1.5 dB in the regulation of the transmitter output power.
- FIG. 1 is a block diagram illustrating an embodiment, which utilizes the adaptable bandwidth concept according to the present invention.
- FIG. 2 is a block diagram, which illustrates an up-link processor.
- the adaptable bandwidth concept requires a closed loop system.
- the terminal communicates with a central, which might be a satellite, a node in a multiple-point system or a base-station.
- the central measures the received power level and supplies the terminal with instructions regarding which bandwidth and which part of the band it may use.
- the central station also manages the portion of the frequency spectrum made free such that it may be used elsewhere in the system.
- the system shall be designed to be so robust that it is sufficient to adapt the bandwidth in practical steps. It will even be possible to combine the adaptable bandwidth with a power tuning, but this makes the system more complex.
- FIG. 1 is demonstrated a block diagram for an embodiment of a terminal utilising a possible implementation of the adaptable bandwidth concept. Except for the variable bandwidth feature the design is similar to terrestrial radio link apparatuses like LMDS (Local Multi-point Distribution System) and satellite terminal concepts.
- LMDS Local Multi-point Distribution System
- the terminal control and interface unit, CIU manages the function of the terminal.
- the CIU is provided with a set of terminals, TRM, which are adapted to be connected to a number of peripheral devices such as external networks, a personal computer, a telephone, a multimedia system, a TV, etc.
- the CIU comprises a central control unit CCU, a base-band processor BP, an up-link processor UP and a down-link processor DP.
- the CCU manages the overall control of the terminal and steers the processors.
- the base-band processor BP performs protocol adaptation, that is performing adaptations between the protocol for communication utilised by the system and the protocol or protocols utilised by the peripherals, for instance the IP protocol.
- the CCU also controls the access, security codes, billing and control of power and bandwidth allocations by addressing data and steering to the different processors.
- the up-link processor, UP presented in FIG. 2 contains data rate control DRC, buffers B, a modulator M, a D/A converter, a frequency synthesiser FS and an up-converter, UIF, to the intermediate frequency IF.
- DRC data rate control
- M modulator
- D/A converter a frequency synthesiser
- UIF up-converter
- power tuning it can be implemented in a number of ways, for example as a fine level adjustment of the IF signal level. A small power tuning of the order ⁇ 1.5 dB will then be sufficient in combination with a control of the data rate in steps with the use of a base of two.
- the down-link processor DP comprises for example frequency generator, base-band down-converter, A/D converter, demodulator, Viterbi decoder.
- the up- and down-link processors are connected to a signal unit S (FIG. 1 ), which comprises an up-converter UC, a power amplifier HPA, a duplexer D, an antenna A, a low noise amplifier LNA and a down-converter DC.
- An incoming high frequency signal from the antenna A goes through the duplexer D into the low noise amplifier LNA and is down-converted to IF frequency in the down-converter DC.
- the IF-signal then goes to the down-link processor DP where the signal is converted to base-band and demodulated.
- the data is then distributed to the proper terminal TRM by the central control unit CCU, which also reads administrative data, for example, information about bandwidth and power levels. Based on this information the data flow on the up-link is modified in the up-link processor UP.
- the up-link IF signal is transmitted and up-converted to high frequency in the up-converter UC.
- the signal is amplified in the power amplifier HPA and is passed through the duplexer D and then transmitted via the antenna A.
- the inventive idea is generally applied for an up-link from a ground terminal to a communication satellite.
- this communication an increased attenuation over the distance is compensated by a stepwise decreased bandwidth at a constant output power of the transmitter.
- the solution results in that power received per unit bandwidth in the satellite may be kept constant and the transmission error rate will be unchanged. Bandwidth not taken by the specific channel may then be utilized by other terminals and the operator gains optimal working conditions and occupancy of the satellite, and consequently a better economical standpoint for the system operator.
- the up-link is dimensioned for a nominal atmospheric attenuation and/or with little margin for other increased propagation loss. This will increase the system capacity during normal propagation conditions. As an example, a reduction of the margin with 10 dB, will during the time the margin is not required, increase the link capacity by roughly a factor 3.
- the maximum available power of the up-link transmitter is concentrated to a bandwidth that is narrowed by the same factor as the increased link attenuation.
- the link capacity is reduced by the same factor, but the signal to noise density including co channel interference will remain constant.
- the frequency band liberated by the attenuated channel can hence be used for other channels for which the capacity is increased, or for additional channels.
- the total system capacity will hence remain constant.
- a second realization applies to CDMA systems.
- the configuration is similar to the first realization, with the exception that the modulation is different, the local oscillator, LO is fixed and the output filter is always appropriate for the transmitted band.
- the link attenuation is increased, the data rate is reduced and the CDMA coding is changed, so that a smaller fraction of the total band capacity is used by the link. This may in the present case best be contemplated as keeping the energy per data bit constant, hence keeping the signal density constant at the receiver location, i.e. the power per bit.
- a combination of power tuning and variable data rate can be used. If the data rate and hence the CDMA coding is changed in steps by a factor of two, the output power tuning can be used to balance the power per bit at the receiver.
Landscapes
- Engineering & Computer Science (AREA)
- Quality & Reliability (AREA)
- Computer Networks & Wireless Communication (AREA)
- Signal Processing (AREA)
- Radio Relay Systems (AREA)
- Mobile Radio Communication Systems (AREA)
Priority Applications (4)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
SE9900195A SE515837C2 (sv) | 1999-01-22 | 1999-01-22 | Adapterbar bandbredd |
PCT/SE2000/000076 WO2000044110A1 (en) | 1999-01-22 | 2000-01-17 | Adaptable bandwidth in a communication system |
AU23373/00A AU2337300A (en) | 1999-01-22 | 2000-01-17 | Adaptable bandwidth in a communication system |
US09/488,314 US6421541B1 (en) | 1999-01-22 | 2000-01-20 | Adaptable bandwidth |
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
SE9900195A SE515837C2 (sv) | 1999-01-22 | 1999-01-22 | Adapterbar bandbredd |
US09/488,314 US6421541B1 (en) | 1999-01-22 | 2000-01-20 | Adaptable bandwidth |
Publications (1)
Publication Number | Publication Date |
---|---|
US6421541B1 true US6421541B1 (en) | 2002-07-16 |
Family
ID=26663486
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US09/488,314 Expired - Lifetime US6421541B1 (en) | 1999-01-22 | 2000-01-20 | Adaptable bandwidth |
Country Status (4)
Country | Link |
---|---|
US (1) | US6421541B1 (sv) |
AU (1) | AU2337300A (sv) |
SE (1) | SE515837C2 (sv) |
WO (1) | WO2000044110A1 (sv) |
Cited By (12)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20020110101A1 (en) * | 2000-12-06 | 2002-08-15 | Nandu Gopalakrishnan | Method for data rate selection in a wireless communication system |
US20050195746A1 (en) * | 2004-03-05 | 2005-09-08 | Eugene Golovinsky | Method of heuristic determination of network interface transmission mode and apparatus implementing such method |
US20070173260A1 (en) * | 2006-01-23 | 2007-07-26 | Love Robert T | Wireless communication network scheduling |
US20080025254A1 (en) * | 2006-07-25 | 2008-01-31 | Motorola Inc | Spectrum emission level variation in schedulable wireless communication terminal |
US20090193137A1 (en) * | 1995-07-14 | 2009-07-30 | Broadband Royalty Corporation | Dynamic quality adjustment based on changing streaming constraints |
US20120129448A1 (en) * | 2010-11-19 | 2012-05-24 | The Boeing Company | Repeater design and verification tool |
US8463314B2 (en) | 2006-01-23 | 2013-06-11 | Motorola Mobility Llc | Power control in schedulable wireless communication terminal |
US9565655B2 (en) | 2011-04-13 | 2017-02-07 | Google Technology Holdings LLC | Method and apparatus to detect the transmission bandwidth configuration of a channel in connection with reducing interference between channels in wireless communication systems |
US9622190B2 (en) | 2006-07-25 | 2017-04-11 | Google Technology Holdings LLC | Spectrum emission level variation in schedulable wireless communication terminal |
US20180091866A1 (en) * | 2016-09-23 | 2018-03-29 | Verizon Patent And Licensing Inc. | Methods and Systems for Concurrently Transmitting Object Data by Way of Parallel Network Interfaces |
US10064132B2 (en) * | 2015-08-19 | 2018-08-28 | Diehl Metering Systems Gmbh | Bidirectional wireless data transmission method |
CN114204976A (zh) * | 2021-11-30 | 2022-03-18 | 中国卫通集团股份有限公司 | 一种通信终端及通信方法 |
Families Citing this family (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
GB0029002D0 (en) * | 2000-11-28 | 2001-01-10 | Nokia Networks Oy | Channels in a communication system |
US6944460B2 (en) | 2001-06-07 | 2005-09-13 | Telefonaktiebolaget L M Ericsson (Publ) | System and method for link adaptation in communication systems |
EP1309105A1 (de) * | 2001-11-01 | 2003-05-07 | Ascom Systec AG | Satelliten/Zellular zwei Betriebsart Endgerät |
Citations (15)
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JPS63262924A (ja) | 1987-04-20 | 1988-10-31 | Mitsubishi Electric Corp | 衛星通信装置 |
JPH02113653A (ja) | 1988-10-22 | 1990-04-25 | Nec Corp | 無線通信装置 |
JPH04144317A (ja) | 1990-10-04 | 1992-05-18 | Nec Corp | 衛星通信地球局の送信電力制御方式 |
WO1993010571A1 (en) | 1991-11-14 | 1993-05-27 | United Technologies Corporation | Ferroelectric-scanned phased array antenna |
WO1993011618A1 (en) | 1991-11-27 | 1993-06-10 | The Commonwealth Of Australia | Feedback communications link controller |
US5590405A (en) * | 1993-10-29 | 1996-12-31 | Lucent Technologies Inc. | Communication technique employing variable information transmission |
GB2310972A (en) | 1996-03-07 | 1997-09-10 | Motorola Ltd | A communication system in which the available band is divided into channels of variable width in dependence on required information capacity |
FR2757725A1 (fr) | 1996-12-20 | 1998-06-26 | Thomson Csf | Procede hierarchique de transmission et de radiodiffusion numerique d'emission radiophoniques |
US5805599A (en) * | 1996-12-04 | 1998-09-08 | At&T Corp. | Adaptive channel allocation system for communication network |
US5812938A (en) | 1994-07-11 | 1998-09-22 | Qualcomm Incorporated | Reverse link, closed loop power control in a code division multiple access system |
US5920545A (en) * | 1995-05-09 | 1999-07-06 | Nokia Telecommunications Oy | Non-transparent data transmission in a digital telecommunications system |
US6298042B1 (en) * | 1997-07-02 | 2001-10-02 | Nec Corporation | Packet switching apparatus adapted to control allowed transmission rate in packet switching network, and method of controlling allowed transmission rate |
US6337849B1 (en) * | 1996-01-09 | 2002-01-08 | British Telecommunications Public Limited Company | Service multiplexer |
-
1999
- 1999-01-22 SE SE9900195A patent/SE515837C2/sv not_active IP Right Cessation
-
2000
- 2000-01-17 WO PCT/SE2000/000076 patent/WO2000044110A1/en active Application Filing
- 2000-01-17 AU AU23373/00A patent/AU2337300A/en not_active Abandoned
- 2000-01-20 US US09/488,314 patent/US6421541B1/en not_active Expired - Lifetime
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JPS63262924A (ja) | 1987-04-20 | 1988-10-31 | Mitsubishi Electric Corp | 衛星通信装置 |
JPH02113653A (ja) | 1988-10-22 | 1990-04-25 | Nec Corp | 無線通信装置 |
JPH04144317A (ja) | 1990-10-04 | 1992-05-18 | Nec Corp | 衛星通信地球局の送信電力制御方式 |
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US5812938A (en) | 1994-07-11 | 1998-09-22 | Qualcomm Incorporated | Reverse link, closed loop power control in a code division multiple access system |
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Cited By (21)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US9832244B2 (en) * | 1995-07-14 | 2017-11-28 | Arris Enterprises Llc | Dynamic quality adjustment based on changing streaming constraints |
US20090193137A1 (en) * | 1995-07-14 | 2009-07-30 | Broadband Royalty Corporation | Dynamic quality adjustment based on changing streaming constraints |
US6930981B2 (en) * | 2000-12-06 | 2005-08-16 | Lucent Technologies Inc. | Method for data rate selection in a wireless communication system |
US20020110101A1 (en) * | 2000-12-06 | 2002-08-15 | Nandu Gopalakrishnan | Method for data rate selection in a wireless communication system |
US7742423B2 (en) * | 2004-03-05 | 2010-06-22 | Bmc Software, Inc. | Method of heuristic determination of network interface transmission mode and apparatus implementing such method |
US20100220625A1 (en) * | 2004-03-05 | 2010-09-02 | Bmc Software, Inc. | Heuristic Determination of Network Interface Transmission Mode |
US7940691B2 (en) | 2004-03-05 | 2011-05-10 | Bmc Software, Inc. | Heuristic determination of network interface transmission mode |
US20050195746A1 (en) * | 2004-03-05 | 2005-09-08 | Eugene Golovinsky | Method of heuristic determination of network interface transmission mode and apparatus implementing such method |
US8463314B2 (en) | 2006-01-23 | 2013-06-11 | Motorola Mobility Llc | Power control in schedulable wireless communication terminal |
US8478328B2 (en) | 2006-01-23 | 2013-07-02 | Motorola Mobility Llc | Power control in schedulable wireless communication terminal |
US20070173260A1 (en) * | 2006-01-23 | 2007-07-26 | Love Robert T | Wireless communication network scheduling |
US20080025254A1 (en) * | 2006-07-25 | 2008-01-31 | Motorola Inc | Spectrum emission level variation in schedulable wireless communication terminal |
US9622190B2 (en) | 2006-07-25 | 2017-04-11 | Google Technology Holdings LLC | Spectrum emission level variation in schedulable wireless communication terminal |
US20120129448A1 (en) * | 2010-11-19 | 2012-05-24 | The Boeing Company | Repeater design and verification tool |
US8725068B2 (en) * | 2010-11-19 | 2014-05-13 | The Boeing Company | Repeater design and verification tool |
US9565655B2 (en) | 2011-04-13 | 2017-02-07 | Google Technology Holdings LLC | Method and apparatus to detect the transmission bandwidth configuration of a channel in connection with reducing interference between channels in wireless communication systems |
US10064132B2 (en) * | 2015-08-19 | 2018-08-28 | Diehl Metering Systems Gmbh | Bidirectional wireless data transmission method |
US20180091866A1 (en) * | 2016-09-23 | 2018-03-29 | Verizon Patent And Licensing Inc. | Methods and Systems for Concurrently Transmitting Object Data by Way of Parallel Network Interfaces |
US10560755B2 (en) * | 2016-09-23 | 2020-02-11 | Verizon Patent And Licensing Inc. | Methods and systems for concurrently transmitting object data by way of parallel network interfaces |
CN114204976A (zh) * | 2021-11-30 | 2022-03-18 | 中国卫通集团股份有限公司 | 一种通信终端及通信方法 |
CN114204976B (zh) * | 2021-11-30 | 2024-03-19 | 中国卫通集团股份有限公司 | 一种通信终端及通信方法 |
Also Published As
Publication number | Publication date |
---|---|
WO2000044110A1 (en) | 2000-07-27 |
SE9900195D0 (sv) | 1999-01-22 |
SE9900195L (sv) | 2000-07-23 |
AU2337300A (en) | 2000-08-07 |
SE515837C2 (sv) | 2001-10-15 |
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